Transmission gear



sept; 24, 1935. H, KOHN 1 2,015,638

TRANSMISSION GEAR H. KOHN TRANSMISSION GEAR sept. 24, 192.5.

Filed Sept. 8, 1953 2 Sheets-Sheet 2 Pai'zentecl Sept. 2 4, 193g UNITED STATES rParleur loFFiclzf 2,015,638 TRANSMISSION GEAR Hans Kohn, StoettenlO. A. Geislingen, `Germany Application september s, 1933, serialfNo. assises In Germany September 13, 1932 19 claims. (ci. u zsa) The invention relates to variable speed transmission gears and more particularly to a variable speed gear which -delivers uniform torque at all adjustments, and the transmission ratio of which is variable continuously between fixed limits,'and

moreover, one in which all the wheels remain also as continuously to vary the speed of said driven` shaft. One of the epicyclic gears may be radially adjustable and arranged so as to act` upon the other or dierential gear, the wheels of the epicyclic gear rolling with respect to one another according to the eccentricity of their adjustment in such a manner that in the limiting conditions y one wheel or the other alone rolls with respect to the other, the wheels, however, rolling mutually at intermediate adjustments. The wheels of the epicyclic gear are respectively directly and in-y directly under the influence of the resistive torque on the driving shaft. This epicyclic gear is, for example, connected between the driven member of the differential gear and the member carrying the planet wheel of the sama-.the epicyclic gear being situated in an extension of the direction of the main shaft of the differential gear or of the driving and driven shafts. TheAmutual rolling of the one wheel, more particularly of the wheel directly subjected to the torque, is preferablyfbrought about by means of a part rotating on the eccentric member.

An example of the numerous possible constructions of the gear. according to the invention is v illustrated in the accompanying drawings," in

' Figure 1 illustrates the gear in plan view,

Figure 2 is a plan View, partlyv in section through the common axis of the driving and driven shaft,

Figure 3 is a section on a larger scale through the epicyclic gear, while y Figures 4 and 5 illustrate diagrammatically,

. the former on the same scale as Figure 3, the epicyclic gear in its two limiting positions as seen from the driven shaft side.

With reference to the drawings, the main shaft train VIll-II of the gear is carried in three bearings I2, I3'and I4 in a frame I5. In this mainshaft'train the member I0 is the driving member, that is the member by meansof which the 5 energy is supplied, for example by way of avgear wheel |00. iThe member II is the driven member which supplies energy and to which the resistive torque is applied.

'I'he driving shaft I0 has fixed on it the bevel 10 wheel I6 ofa differential gear, the driven wheel II of which drives a shaft I1. The shaft I1 has lllxed on it a gear wheel I8 which engages with has xed on it-a plate 23 which, by means of,

dovetails or in any other desired manner, acts as a guide for a slide 24 which displaceable in a radial direction with respect to the guide plate 23. The slide 24 is formed, on its side remote 20 from the guide plate 23, as a disc-like member 25, the periphery of which forms a bearing for a toothed ring 26 having internal and external teeth and on which bearing the ring may rotate freely. A pin 2,1 is fixed on the disc portion 25 of 25 the slide 24 and displaced from its centre, on which pin a planet wheel 28 rotates freely. The disc portion 25 overlaps the toothed ring 26 outwardly at 29 in such a manner that double vpinions 30, 3-I and 32, 33, fixed on the common shafts 30 30T or 32 respectively, can be mounted in bearings in it, the pinions 30 and 32 engaging in the external teeth of the toothed ring 26 while the other coaxial pinions 3| and 32 engage in an internally toothed ring 34 yon a casing 35 surround- 35 ing the slide gear, which casing is mounted so as to be freely rotatable on the toothed ring 26. The pinion 32 and the planet pinion 28 are both mounted on the same radius of the member 25, 29, so that the points of engagement of the planet 40 wheel 28 and'of the toothed ring 26 areat a constant distance on this radius. f

The planet wheel'28 turns the driven shaft II directly by means of an articulated shaft or the like 36. Similarly, the casing 3 5 is connected byl 45 means of a sleeve-like articulated shaft 31, which surrounds the articulated shaft 36, with a gear wheel 38 which is freely mounted on the driven shaft II. The gear wheel39 engages with this gear wheel 38 and is xed on the intermediate 50 vshaft 22. It is therefore connected wih the gear wheel I8 by way of the gear wheel I9 which is which in the example illustrated pa'sses through the hollow 'first intermediate shaft 22 and has fixed to its 'other end a gear wheel 43 which engages' with a gear wheel 4. The gear wheel 44 is secured to the casing 41 which carries the rotating wheels 45, 46 of the differential gear, the rotary wheel carrier.

'I'he transmission ratio is varied as a'result of displacement of the slide 24 on its guide plate 23. This radial displacement of theslide 24 may be effected during the rotation of all parts, for example as illustrated, by means of a shaft 48 which passes through the hollow shafts I8 and I1. An angular displacement can be imparted tothe shaft 48 with respect to the shafts I 8 and I1 during rotation by means of a lever 58. For this purpose, the lever 58 engages with an annular groove 49' in a sleeve 49 bymeans of a ring 58 connected with the lever by pins 58", the sleeve 48 being guided axially in grooves I8' in the shaft I8 and therefore rotating with the shaft I8, This sleeve 49"has inclined grooves 49" in which engage pins 48 in the shaft 48, which shaft is secured against axial displacement at 48". Ihe

inner end of the shaft 48 passes through the guide plate 23 and engages, by means of a small crankor a cam 48, in an opening24' in the slide 24, which opening is somewhat elongated corre-'- ring 26 rollsitself along onl the wheel 28 by means of its internal teeth so that the wheel 28 be-v comes a stationary wheel, while in the other limiting position, which -is illustrated in Figure 4, the wheel 28 rolls itself along the stationary, toothed ring 26.

As a. result or the planet wheel za remaining stationary (the limitingposition according to Figure 5), the inner articulated shaft 36 and the driven shaft Il which is connected to it also remain stationary. This shaft II is connected by the intermediate gear 48, 4I, 42, 43, 44 with the rotary wheel carrier 41. As, therefore, this carrier 41 is also stationary, the rotary'motlon of the drivingl shaft I8 is thus transmitted at the.

full speed to the gear wheel I1 by way of Athe 'wheels 45, 46. The shaft I1 with the slide '23 and its member 25, `29,,tlfierefore rotates rapidly.

VThe shafts`4` d'rtht; piment n, 3|, n; as, which are mounted in beariigsiln the member, 29', naturally revolve in a circular path at the same number of revolutions as the plate 25, 29. If the casing 35 connected to theouter articulated shaft 31 were'to rotate at the same speed as the plate 25,

29, the toothed ring 28 would be ean'ied round' by th pinions com, s2, n at vthe same rotary speed as that of 25, 29. Now the number of external teeth on the toothed ring 26 is less than the number ofteeth .on the larger internally-toothed ring 34, and the speed of revolution of the pinion shafts is the same as that of the member 25, so that-the outer ring 34, 35, because of its greater diameter, must run faster than the double toothed ring 28, in order to bring about a complete rolling of the toothed ring 26 on the wheel 28, whereby the latter, as there is no resistance* to its movement at the internal teeth of the toothed ring 26, is compelled to become stationary. 'I'his complete rolling of the toothed ring 25 on the wheel 28, is brought about by reason of the fact that the casing 34, 35 is connected'with the intermediate gear 38, '39, I9, I8 by means. of the articulated sleeve 31. The wheels 38, 39 ofthis intermediate gear are such that the wheel 38 runs faster than the wheel I8.

The other limiting case is that in which the driven shaft I I is given the maximum number of revolutions. In this case the revolutions of the driving shaft -i8 distribute themselves between` the rotary wheel carrier 41 and the shaft J1. In view of the intermediate gear, 44, 43, 42, 4I, 48, the number ofu revolutions of the 4rotary wheel carrier 41 corresponds to the number of revolutions of the Adriven/shaft Il. Although therotary wheel carrier 41 rotates .at its maximum speed, part of the revolutions of the shaft I8 is, 20

as aforesaid, transmitted by way of the wheels 45 and 46, to the wheel I1 and the shaft l1 which, however, now runs substantially slower than'in the other limiting casein which the rotary wheel carrier 41 is stationary. In the present hunting 245 ing is acted upon by way of the articulated shaft' 31, and the intermediate gear 38, 39,'22, I9 by the gear wheel I8 of the driven wheel I1 of the-differential `gear in such amanner that the toothed ring 26 cannot follow the planet wheel 28.

The member 25, 29 also rotates with the shaft o I1 (but slower than in the limiting case of Figure 5). Now, however, as a result of the transmission between the wheels`38, 38, the speed of rotation of the casing 35 is greater than that of the slide member 25, 29 to the extent that the toothed ring. is held back to such an extent that the planet wheel 28 endeavours to trike it up in the opposite direction of rotation. Thus, the

toothed ring 26 becomes' a stationary member,

around which the point of engagement of the planet wheel 28 vin the internal teeth 26, and the points of engagement of the pinions 38, 32 in the external teeth of the ring 26and in fact of all points of engagement in the same radial plane-revolve continuously.

5 In the llimiting case villustrated in Figure 5 the 5 plate member 25, 29 is, as regards'the planet wheel 28, merely a bearing member that rotates round this wheel without eect, because the centre of the twheel 28 coincides with the axis A-A ofthe shaft train I8. On th'e other hand, .the plate 25, 28 is in this sition an eccentric body with respect to the toothed ring 26, and swings this ring round with it and thus causes rolling of the ring about the planet wheel 28.

In the other limiting case, that of Figure- 4,011 65 the other'hand, the plate member 25, 29 forms, with respect to the toothed ring 26, a bearing member rotating ineffectually in the interior of this ring, while this member 25, 29 is a crank disc 70 termediate these two limiting positions, the rolling of one of the two'wheels 26, 28 with respect 7g to the other takes place to the extent that the member 25, 29 acts as an eccentric regarding the wheel 26 or 28.

It will be seen that the gear involves the principle of distributing, as desired, the revolutions fore of the driven shaft Il -is brought about by means of a rotating toothed wheel gear 2 6, 28 one or otherof the two wheels being stationary alternately in eachof the two limiting cases while the other takes over the full rolling motion. .In intermediate positions, on the vother hand, a simultaneous mutual rolling of the two wheels 26, 28 takes place.

The scope of the'invention is not limited to the details of the constructional example described which may be varied both as regards the construction and arrangement of its individual parts. For example, the gear may be so constructed that the parts of the intermediate shafts 22, 42 are also displaced in the axial direction A-A.

I claim:-

1. In an Yapparatus of the class described, a.V

d riven shaft, a variableLspeed gear comprising' a differential gear and an epicyclic gear including at least two continuously interengaging wheels, both said gears being connected to 'said driven shaft, means'whereby said epicyclic gear acts on part `of said differential gear, and means whereby said two interengaging wheels are respectively directly and indirectlyracted upon by the resistive torque'of the driven shaft, saidepicyclic gear being adjustable so'that itswheels -roll with vrespect to one another according to the eccentricity of the adjustment of said interengaging wheels whereby said driven shaft may be rotated at a speed that is continuously variablewithin limits.

2. In an apparatus of the class described, a

driven shaft, a variable-speed gear comprising a differential gear including driving and driven wheels and at least one planet wheel engaging them and mounted on a rotary carrier, and an epicyclic gear including at least two continuously interengaging wheels, both said gears being connected to said driven shaft, and said epicyclic gear being connected tween said driven differential wheel and said rotary carrier, and means whereby said two interengaging wheels are respectively directly and indirectly acted upon by the resistive torque of the driven shaft, said epicyclic gear being adjustable-so that its wheels roll with respect to one another according to the eccentricity 3. A variable-speed gear according to claim 2, in which said epicyclic gear consists of `an internally toothed ring and a planet pinion engaging therein, said toothed ring `being rotatably connected with said driven differential wheel, and

- said planet pinion beingrotatably connected with said rotary carrier.

4. Avariable-speed gear'ac'cording to claim 2,v

in which saidepicyclic lgear is arranged between the coaxialv driven differential wheel and said driven shaft, said epicyclic gear being mountedl on a 'member that is connected for rotation with within limits.

l said driven differential wheel.

vof the adjustment of said interengaging wheels whereby said. driven shaft may be rot-.ted at a speed that is continuously variable within limits.

said driven differential gear by means of a slide and said planet pinion being connected for rotation with said driven shaft, said member being displaceable so as to make either said toothed ring or said planet wheel coaxial with said driven dif- 5 ferential wheel and said driven shaft, or brought into any intermediate position whereby said driven `shaft may be rotated at a speed that is continuously variable within limits.

5. A variable-speed gear according to claim 2, lo

in which said epicyclic gear consists of an internally and externally toothed ring and a planet pinion engaging in the internal 'teeth thereof, said toothed ring being rotatably connectedexternally by means of a' pinion with said driven difIerl5 ential wheel, and said epicyclic gear being mounted on a' rotary member that is connected for rotation wth said driven differential gear, said member c ying said pinion and said planet pinion on the same radius of said member, so that 20V the points of engagement of the teeth ofsaid planet pinion and said toothed ring are at a constant distance o'n the said radius.

6. A variable-speed gear comprising driving and driven shafts, a differential gear including 25 driving and driven wheels and atleast one planet "wheel engaging them and mounted on a rotary carrier, a member carrying an epicyclic gear including a rotatable internally and externally toot ed ring and a planet pinion continuously engagi g the internal teeth of said ri ng, a casing rota bly mounted on said -member coaxialwith. said g, internal teeth on said casing, at least one pinion interconnecting theginternal teeth of 1 said casing with the external teethof said toothed 86 ring, said pinion being carried on a shaft mounted on 'said member, means whereby said planet' pinion' is'- connected for' rotation withsaid driven shaft, means' rotatably connecting said casing with said driven differential wheel, means rotat- `40 ably connecting said rotary carrier' withv said driven shaft, said member being displaceable with respect to said driven shaftso thatv either said planet pinion or said toothed ring may be made coaxial therewith or brought into any intermedi- 45 ate position whereby said driven shaft may be rotated at a speed thatis continuously variable 7. A variable-speed gear according to claim 6, in which saidA means whereby said casing is rotat- 50 ably connected with said driven dierential wheel and said means whereby said carrier is rotatably connected with said driven shaft, comprises shafts. and gear wheels.

8. A variable-speed gearaccording to claim 6, '55 l in which said driven differential' wheel `drives said memberthrough' a sliding connection, said member being adjusted by means of .an eccentric device rotated by a shaft passing coaxially thrbugh 9. Ay variable-speed gear according to claim 6, wherein said means .rotatably connecting said casing with said driven differential wheel comprises a gear wheel'freely rotatable on said driven shaft, articulatedvmeans connectingfor rotation 06 said casing with said gear wheel; a gear wheel connected to said driven differential wheel, 'and a 'shaft parallel to said driven shaft, said shaft carrying gear wheels meshing with said freely rotatable gear wheel and said gear wheel driven 'l0 by said differential driven wheel.

- 10. A variable-speed'gear according to claim "'6, wherein said means lforrotatably connecting said rotary carrier withsaid driven shaft Acomprises a gear wheel fixed on said driven shaft, a gear wheel I5 allel to said driven shaft and gear wheels on said` last-mentioned shaft meshing respectively with said gear wheel and said driven shaft, and said gear wheel on said -rotary carrier.

11. A variable-speed gear' according to claim 6, in which said driving' shaft, a shaft connecting said driven differential wheel with said member, and said driven shaft, are mounted coaxially in bearings ina common ame.

12. A variable-speed ear comprising 'drivi -and driven shafts, a di erential gear including driving and driven wheels and at least one planet wheel engaging-them a d mounted on a rotary carrier, a member carr f g an epicyclic gear in- -cluding an internally toothed rotatable ring and a planetrpinion engaging in the internal teeth of said ring, means whereby said member vis driven from said driven differential wheel,means whereby said toothedring is rotatably connected with said driven differential wheel, and means whereby 'said rotary carrier is rotatably connected with said driven shaft, said member being adjustable so' as to bring either said planetpinion or said tooth d ring coaxial-with said'driven .shaft and into a y intermediate position whereby said driven shaft may be rotated-at a speed that is variable continuously within limits.

13. A variable-speed gear according to claim 6, in which said driven differential wheel is coaxial with said driven shaft, and said driven differential wheel drives said member through a slidingcon# necton, said planet pinion being connected to said driven shaft by an articulated shaft.

14. A variable-speed gear including driving and driven shafts,VP comprising a differential gear including driving and driven'wheels and at least one planet wheel engaging them and mounted on a rotary carrier, a member carrying an epicyclic gear, including a toothed ring and a planet wheel engaging it internally, means connecting for ro- -tation one member of said epicyclic gear to the driven shaft, means rotatably connecting the other member of. said icyclic gear to said driven differential wheel/mep L eans rotatably connecting said driven shaft and said rotary carrier, and means for driving said member from said driven dierential wheel, said member being adjustable so as,to bring either' said toothed ring or said lplanet wheel coaxial with said driven shaft or i said driven differential vwheel and into any intermediate psition whereby saiddriven shaft may be rotated at a speed that is variable continuously within limits.

M 15. A variable-,speed gear comprising a differential gear and an epicyclic gear including at least iwo continuously.interengaging wheels, said diifer. .ential gear and said epicyclic gear both being connected tov the driven shaft, means whereby said epicyclic gear acts on part of said differential gear,

means whereby said two interengaging wheels are respectively directly and indirectly acted upon by the resistive itorque of the driven shaft, means for 16. A variablefspeed gear comprising driving and driven shafts, a differential gear including driving and driven wheels and at least neplanet wheel engaging them and mounted on arotay carrier, a member carrying an epicyclic gear including at least two continuously interengaging wheels, means connecting for rotation one of said interengaging wheels with said driven shaft,.

. means for driving said member from said driven differential wheel, and means rotatably connecting the other ot said interengaging wheels with said driven differential wheel, said member being adjustable so as to bring either said toothed ring or said planet wheel coaxial with said driven shaft or said driven differential wheel and into any intermediate position whereby said driven Ashaft may be rotated at a speed that is variable continuously within limits.

v1'1. A variable Ispeed gear comprising a driving shaft, a 'driven shaft, a differential gear and an epicyclic gear interconnected therewith extend- *ing between said driving and drivensh'afts, said 35 last-mentioned epicyclic gear rcomposed of two circular gear members in permanent rolling en- "gagement one within another, with the relative eccentricity of said gear members being adjust-V able.

18. A variable speed gear comprising a' driving shaft, a driven shaft coaxial therewith, a differ- I `ential gear and an epicyclic gear interconnected .therewith extending between said driving andA driven shafts, said last-mentioned epicyclic gear composed of two circular gear members in perma- \nent rolling engagement one within another, the eccentricityof each of said circular gear members being adjustable with respect to the longitudinal axis of said driving and driven shafts.

19. A variable speed gear comprising a driving shaft, a driven shaft, a differential gear and a rolling epicyclic gear interconnected therewith 'exf tending between said driving and driven shafts,

said rolling gear including at least two interengag- $5 ing wheels, a rotatable bearing member for said rolling gear, meansfor adjusting the eccentricity of said bearing member and thereby that of said interengaging wheels, and means for varying the speed of rotation of said bearing member. i

- HANS KOHN.

eccentrically adjustable n 

